Online Sequencer Forums

Full Version: spectrogram because why not
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
This is my first post here so please tell me if I'm doing it right or whatever, anyways here's a cool spectrogram that I made because I was bored






















(10-22-2020, 07:54 AM)Ourobius Wrote: [ -> ]I'm afraid you may not be doing it right.
darn
Actually, this isn't necessarily wrong.

I used a website to try to play back the sound of this spectogram. (As you probably know, a spectogram shows frequency over time.)
Here is the website I used: https://nsspot.herokuapp.com/imagetoaudio/

At first it didn't sound like anything. But then I found that the site plays black and white spectograms more easily, so I made your original image black and white and I was able to hear a little bit of sound. I have attached the B&W version that I made. On the website, I made sure to bring the "length" value to something like 20, and the "density" value to 1. I also used the "selected area" option, and cropped out most of the top of the image where there is no data, so the overall max frequency levels are higher throughout the entire sample.

However, I was never able to get any kind of sound without a large amount of distortion. I don't think this has anything to do with your image. I tried making a few other spectograms myself, but never was able to hear any of the original audio back. I think that the site that I found just doesn't work quite right. Or I don't know how to use it.
I can't attach wave files in these forums apparently. I will post the audio file that I was able to get from the black and white version of your file on discord. If you have a discord, you can find it when I post it in the OnlineSequencer Discord Server, in the channel #os-discussion.
what noise are you trying to make
Depending on the max frequency used, notes should not be placed linearly. Online Sequencer's editor shows notes as having a linear frequency curve. However, with a real-world spectrum, this does not hold true. Wikipedia has a list of piano key frequencies here, and you may find that if you analyze the frequencies, they will start out having very small gaps between them at the lowest notes of the piano, and that as you scroll up the page from the bottom, you will see the frequencies start to spread out as the notes increase in frequency.

Here is something I just made after coming up with a template for each pitch of the musical pitch frequency for creating spectograms. Can you guess what song it is? Since I used a small window between C6 and C7, there isn't too much distortion between the gaps between the notes, so it looks relatively uniform. If you were to download this image and upload it into https://nsspot.herokuapp.com/imagetoaudio/ (or another website that can play spectograms), it should play the song that I tried to write.

I have also attached another image file. The second file shows my attempt at showing how octaves appear non-linearly on the frequency spectrum. In this image, each red line marks the note C. The red line at the very bottom of the image is C2. The one just above that is C3, Middle C. The red lines continue to hit, and the very top of the image goes all the way up to where C8 would be. This shows how on a linear grid spacing, frequencies start to grow away from each other. The wikipedia page that I linked has an equation at the top of the page. This equation is logarithmic, which helps to understand the mathematics of why this happens.